Saw sharpener



Jan. 18, 1949. A. w. MALL 2,459,233

' SAW SHARPENER Filed Sept. 28, 1944 4 Sheets-Sheet l mill-Ill;

uill-m mrrawron 4/ av WXMQ JTTURNE) A. W. MALL SAW SHARPENER Jan. 18, 194%.

4 Sheets-Sheet 2 Filed Sept. 28, 194-4 5 Rim ATTORNEY Jan. 18, i fi. H A, w. MALL 2,459,233

SAW SHARPENER Filed Sept. 28, 194-4 4 SheetsSheet 3 INVE/V 729R 63% wmia @Y W Z LL ATTORNEY Jan. 18, 1949. w MALL 2,45%,233

SAW SHARPENER Filed Sept. 28, 1944 4 Sheets-Sheet 4 FIG. f

INVENTOR Qa/wme BY Wfm ATTORNEY Patented Jan. 18, 1949 SAW SHARPENER Arthur William Mall, Flossmoor, Ill., assignor to Mall Tool Company, Chicago,

of Illinois 111., a corporation Application September 28, 1944, Serial No. 556,231

18 Claims.

My invention relates to saw sharpening machines and has for its general objective, the provision of a sharpening machine which may be used for sharpening continuous link-toothed cutting chains and other types of saw blades.

My invention also has as the provision of a new method for sharpening cutting chains and saw blades.

The specific objects and advantages of my saw sharpening machine and method will be herein- Fig. A is a plan view of the turntable device,

parts of which are shown in section;

Fig. is a sectional view of the turntable device taken on line 5-5 of Fig. 3;

Fig. 6 is an enlarged fragmentary detail view of the turntable device as shown in Fig. 3 illustrating the grinding operation;

Fig. '7 is a fragmentary detail View taken on line l-'l of Fig. 6;

Fig. 8 is a detail view of the tooth locating lever;

Fig. 9 is a detail view of a modified form of my invention for sharpening circular saw blades; and

Fig. is a detail side view of the device shown in Fig. 9.

I have provided a main supporting casting I, which may be secured by means of bolts 2 to any suitable bench or table, or if no table or bench is available then'it may be secured to a tree or other vertical object by means of theleg members 3 which may be secured to casting i by any suitable means. Casting I is provided with a pair of vertically extending side walls 4 and 4a and a front Wall 5. Casting l is provided with a pair of bosses 6 and I, through which holes are drilled so as to receive rod 8. The side walls A and 40 are also provided with holes axially aligned with the holes in bosses B and l and rod 8 extends across the entire width of casting I protruding through each of the side walls.

The hole which extends through side Wall 4a and boss 1 is threaded so as to receive the threaded end of rod 8. Rod 8 is therefore axially movable relative to casting l, by turning handle 9.

its general objective,

ill

A second casting I0 is provided with a bifurcated portion terminating with arms H and I2. Both arms H and I2 are pivotally mounted on rod 8. A collar i3 is rigidly secured to rod 8 by a pin 14 extending through said rod. A compression spring I5 is under tension at all times,.thereby urging arm l2 away from collar l4. Arm H is thereby continually biased against collar 13. The position of casting l0 relative to casting l is thereby governed by the position of collar l3. The reason for this adjustment will be hereinafter described.

Casting H) has an upwardly extending wall portion I! and a downwardly depending wall portion l8 terminating in an outwardly extendingjbase portion l9.

An adjustment screw is threaded through the upper wall portion H and its free end is adapted to abut against the front wall 5 of casting 2. A lock nut 2i secures adjustment screw 20 in any predetermined position of adjustment. The function of adjustment screw 20 will be hereinafter pointed out.

A second adjustment screw 22 is threaded through the lower wall portion l8 and its free end abuts against wall 5. Lock nut 23 secures adjustment screw 22 in any predetermined position of adjustment. The function of screw 22 will be hereinafter explained.

A third screw 25 is located at the upper end of the upper wall portion H. The head 26 of screw 25 is adapted to abut against wall 5. A collar 21 is threaded onto screw 25 and is locked in position by nut 28. Collar 2'! has a threaded stem 29 which is loosely threaded into threaded bore 31 in wall portion I! so as to be pivotal relative thereto. Pin which is pressed into wall portion ll limits the pivotal movement of screw stem 29 in the threaded bore 3| as a result of collar 21 abutting against pin 3!]. The function of screw 25 will be hereinafter explained.

The base portion 19 of casting H) is provided with an arcuate rib 32 which mates with the arouate groove 33 formed in turntable 34 whereby turntable 34 may be rotated relative to casting ll] about an axis common to the axis of turntable 34 and to the axis of arcuate rib 32. A second arcuate rib 35 is formed in the upper surface of turntable 34 and its axis is common to the axis of turntable 34.

A screw 36 extends through the base portion l9 and also through bosses 31 and 38 formed in said base portion. The threaded end of screw 36 is threaded into a clamp bar 40. One end of clamp bar 4'0 is loosely received in a slot 4! 35 to the right, thereby causing clamp bar 49 to become tightly biased against rib 35 against the opposing bias of base portion I9 against the underneath surface of turntable 34.

At the upper end of casting I are a pair of horizontally aligned bosses 45 and 41 which receive a pair of parallel rods 48 and 49 by pressed fit. At the outer ends of said rods is a bracket assembly 59 Which is slidably mounted relative to rods 48 and 49. A spindle housing 5| is securely fastened to the bracket assembly 59 so as to be movable therewith. The grinding wheel 52 is rotatably supported by anti-friction bearings (not shown) located within the spindle housing. At the other end of the spindle housing .is a pulley groove 53 which may be drivingly connected to a power unit (not shown) by means of belt 54.

A clamp bar 55 rests upon rods '48 and 49 and is removably connected to the bracket assembly 58 by means of bolt 56. When it is desired to adjust the grinding wheel 52 and bracket assembly 59 longitudinally relative to rods 48 and 49, bolt 55 is loosened and bracket assembly 59 may be manually moved longitudinally of rods 48 and 49. When the grinding wheel and bracket assembly are moved to the desired position of adjustment, then bolt 56 is re-tightened thereby causing clamp bar 55 to securely fasten said bracket assembly in its selected position of adjustment.

By using two parallel rods 48 and 49, I prevent any possibility of pivotal movement of bracket assembly 59 about the axis of rods '48 and 49, thereby assuring that grinding wheel 52 is always maintained in a true vertical plane.

A bracket 58 prevents bracket assembly 59 from sliding oil" the ends of rods 48 and 49 and maintains rods 48 and 49 in parallel relation to each other.

A counterbalancing tension spring 59 is suspended between rods 48 and 49 and base portion 49 by means of bolts 60 and 6|. Bolt 60 is supported relative to rods 48 and 49 by'bars 62'and 93 which extend transversely of said rods. Bolt 5| extends through base portion 19 of casting Ill. The ends of spring 59 are secured to bolts 60 and 5| and said spring is always under tension so that casting I6 and turntable 34 and all of the parts carried by said casting and turntable normally swing about pivot 8 to an upward position in which screws 25 and 29 abut against wall 5 as shown in Fig. 1. When the weight of the chain 54 or saw or saw blade to be sharpened is added to turntable 34, then the tension of spring 59 is overcome and turntable 34 and its associated parts swing'about pivot 8 to a downward position until screw 22 abuts against wall 5.

Turntable 34 is provided with a circular base 65 and an upwardly extending wall 69. Wall'96 isprovided with two'bosses'61 and 68. A pair of pins 59 and 18 are pressed into wall 66 through bosses 91 and 68. The heads 1| and 12 of pins 99 and 19 protrude outwardly from the wall 65 and form a bearing support'for segment 13. Segof slot 14.

ment 13 is provided with an arcuate slot 14. The arcuate periphery 15 of segment 13 is generated from an axis which is common to the axis of slot 14. Likewise, an arcuate line drawn through the axes of pins 69 and 19 is generated from the same axis as periphery 15 and slot 14. A bolt 11 has a squared shoulder portion 18 which fits snugly enough in slot 14 so as to eliminate play, but loosely enough to allow segment 13 to be rotated relative to wall 68 within the limits When segment 13 is rotated the "periphery 15 continually rides on the pin heads 1| and '12, thereby receiving bearing support therefrom. Segment 13 is provided with indicator marks 19 and pin head 1| has a locating mark inscribed therein.

Bolt 11 is threaded at one end and receives internally threaded wing nut 8|. Thus, when it is desired to rotate segment 13 relative to Wall 86,

wing nut 8| is turned to the left and when segadjustment, wing nut 8| is turned to theright thereby tightening segment 13 against wall 55.

Segment 13 forms one portion of a casting 82. Said casting has an outwardly and transversely extending bar 83. Said bar has a base portion 84 and a wall 85 extending upwardly at right angles to the base portion. The base portion '84 has an upwardly extending block 89 for supporting the saw chain clamping device.

Secured to base 84 by bolts 89 are a pair of bars 81 and 88 which conform to the surface contour of base 84 as best viewed in Fig. 3. Said bars 81 and 88form a wall 99 (best viewed in Fig. 1) opposite wall 85. Walls 85 and 99 and base 84 form a groove in which the depending tongues 9| (see Fig. 6) of chain teeth 92 ride. The width of said groove may bevaried by loosening bolts 89 and moving bars8'! and 88 inwardly or outwardly within the limits of slots '94.

The inner ends of bars 81 and 88 are spaced from each other so as to provide parallel walls within which clamping block is free to slide back and forth. Block 95 .is provided with a centrally located, internally threaded bore which receives the threaded end of screw member '95. Screw member 96 is slidably received in a central bore 91 extending'through support block'sfi. The outer flattened end of screw member. 981s pivotally secured by pin )4 within the bifurcatedend of handle 99. The inner end of each fork I00 is rounded at |9| to provide a bearing surface for riding against wall I92 of block 85. Bearing surface |9| serves as a cam. when handle 99 55 is manually push-ed downwardly, therebycausing :position to be sharpened, it is anchored inposition by clamp block 95 engaging the depending tongues 9| of two successive chain teeth 92.

Handle 99 is normally maintained in a downward position thereby causing clamp block 95 to be maintained in a retracted position. 'When it is desired to moveclamp block 95 in chain'clamping direction, handle 99 is moved upwardly to the position shown in Fig. 5. Compression springs 99, which are always under tension, cause clamp block95 to be biased against the tongues '92 of the cutting chain. It will be noted that block 86 is provided with a pair of bores N9 95. Thus when chain 94. V

which are axially aligned with a pair of bores III in clamp block 95. Compression springs I59 are mounted in said bores; It will be noted that clamp block 95 may be adjusted relative to screw 95, thereby varying the tension of springs I59. This adjustment is accomplished by rotating handle 99.

In order to assure that each tooth is located in the proper position before being anchored by clamp block 55, I have provided a locating finger I I4. Said finger I I4 is formed in a bar II5 which is secured to a cross piece II6 of bracket device II'I. Said bracket II? consists of a pair of axially aligned hubs H8 and H9 which embrace the block 86. A pin I 20 extends through block 86 into hubs II8 and H9 so that bracket II I may be pivotally swung around said pin I20. Said bracket II'I has a pair of arms I2I and I22 which merge with cross piece II 6. Said bracket Ill also has an outwardly extending arm portion I23 the reason for which will presently appear, Said arm portion I23 extends inwardly to form a lip I24 which abuts the underneath surface of block 88. A torsion spring I25 is coiled about hub H8 and one end of said spring is secured to the underneath side of block 86 by means of a screw I21 shown in Fig. 3 and shown in dotted lines in Fig. 8. The other end of torsion spring I25 overlaps arm I2I, thereby causing bracket II! to be normally maintained in retracted position as shown best in Fig. 1. Bracket II! is moved about pivot pin I25 into tooth locating position by applying manual pressure against the underneath side of arm portion I23.

Referring to Fig. 6, I have shown the different types of cutting teeth which make up cutting chain 64 and the three angular faces on each tooth. For purposes of clarification, I have desig nated these angular faces as the face angle, hook angle and clearance angle. angle is designated as I28, the hook angle as I29 and the clearance angle as I 35. My sharpening machine is primarily intended for grinding only the face angle I28 and hook angle I29 as it is rarely necessary to grind the clearance angle I35. It is also to be noted that the hook angle and face angle are ground simultaneously in the manner hereinafter described.

Method of operation When it is desired to sharpen a cutting chain such as is shown in Fig. 6, the method of procedure is as follows:

Itwill first be noted that cutting chain 64 is made up of inner link teeth 92, called raker teeth and outer link teeth I! called cutting teeth and the sequence is made up of four different types of teeth, consequently every fourth tooth is identical in construction. Cutting chain 64 is first placed into the guide groove I55 (as best shown in Fig. 6). Then the grinding wheel '52 is adjusted longitudinally of rods 48 and as by loosening bolt 55 and manually moving bracket assembly 59 relative to rods 48 and 45. Then turntable 34 and casting II] are swung as a unit about the axis of rod 8 and chain groove I approaches the bottom edge of grinding wheel 52 in an arcuate'path (as determined from axis of rod 8) shown by arcuate line I55. The lowest point on the underneath edge of the grinding wheel 52 (which point is designated as I5!) is then aligned with guide groove I55 viewing Fig. 1. Then bolt 56 is retightened, thereby securing grinding wheel 52 in a fixed position. It is to be'noted that asth'e grinding wheel 52 wears The face that finger II 5 will down, it becomes reduced in diameter, thereby changing the aligned position of point I5I relative to chain guide groove I05. Consequently, it becomes necessary to occasionally re-adjust grinding wheel 52 longitudinally relative to rods 48 and 49 so as to re-align point I5I with guide groove I 05.

The second step is to move handle 99 upwardly to the position shown best in Fig. 5, thereby causing clamp block 95 to anchor the cutting chain in a fixed position in guide groove I05.

The next step is to adjust segment I3 rotatively relative to the wall portion 66 of turntable 34. This is accomplished by loosening Wing nut 8i and manually rotatin segment I3 within the limits of slot 75. The indicator marks I9 when aligned with the indicator mark on pin head II accurately determine the angular position of segment I3 relative to wall 66. Likewise rotation of segment I3 causes cutting chain 64 to assume the tilted position shown in Fig. 6 and the hook angle I29 of the cutting teeth assumes a vertical position in alignment with the vertical position of grinding wheel 52. Wing nut M is then retightened thereby securing segment 73 in a fixed position of adjustment relative to wall portion 66.

The next step is to rotatively adjust turntable 34 relative to casting It by loosening screw 35 and manually rotating said turntable. The indicator marks 53 on turntable 34 when aligned with the indicator mark 44 on casting I0 accurately determines the angular position of turntable 34 relative to castin Ill, thereby adjusting the face angle I25 of the chain tooth so as to be fiat against the side face of grinding wheel 52. When this is accomplished screw 36 is retightened thereby securing turntable 34 in a fixed pgsition of rotative adjustment relative to casting The next step, then, is to manually swing bracket II'I about its pivot pin I25 (preferably by inserting a thumb or finger under arm portion I23) until locating finger I I5 is inserted into one of the openings between the two cutting teeth (the opening referred to is the opening into which grinding wheel 52 is inserted as shown in Fig, 6). Cutting chain 64 is then manually moved through groove I 55 until the outermost cutting tip I55 engages locating face I54 of locating finger H4. The manual pressure on bracket II 'a' is then released and torsion spring I25 causes bracket II? and locating finger II4 to swing back into its retracted position as shown in Fig. 1. It is to be noted that locating face I54 of locating finger H5 is beveled oif slightly so not drag against cutting tip I I5 during retracting movement of bracket I IT.

The next step is to adjust turntable 34. and casting 'II'J laterally relative to casting I by rotating rod 8 by means of handle 9. This adjustment, as hereinbefore described, causes cutting chain 54 to be moved in a direction which is the same as the axial movement direction of rod 8 accomplished during rotation of rod 8. I Cutting chain 5 3 is thereby adjusted in a laterial direction relative to grinding wheel 52 and the amount of metal to be ground oil of each tooth is accurately determined by the rotation of rod 8. V The amount of metal to be groundoff of each tooth may be best adjusted by starting up grinding'wheel 52 and thereupon rotating rod 8 simultaneously while grinding the tooth which is in grinding position. I

The next'step, then, is to loosen lock nut 2| and adjust screw 20 so that the free end of screw block 95. again until the fourth succeeding tooth reaches 20 abuts wall at the moment when the bottom edge of grinding wheel 52 reaches the desired depth within the openings between the cutting portions of the chain teeth. The desired depth is shown in Fig. 6 wherein the point i5lk of grinding wheel 52 just grazes the base .1530 of the cutting teeth. It will be noted that as the grinding wheel 52 wears down and becomes reduced in diameter, screw will have to be re-ad-- justed to permit turntable '34 to swing further upwardly about the axis of rod 8.

Adjustment screw 22 limits the downward movement of turntable 34 about the axis of rod 8 and serves to maintain the cutting chain in a position near the grinding Wheel, so that turnis then manually moved forward until tip H5 of tooth I70 grazes face I50 of locating finger H4. Then handle 09 is moved upwardly to position shown in Fig. 5 and clamp block 95 is anchored against the depending tongue 9| of tooth H0. Locating finger H4 is then retracted andtooth H0 is sharpened. As previously pointed out, counter-balancing spring 59 facilitates manual movement of turntable about axis of rod 8 for bringing tooth H0 into the grinding wheel. When tooth [l0 is sharpened, the manual pressure on turntable 30 is released and tooth I10 moves away from the grinding wheel. Handle v99 is then pulled downwardly, thereby retracting clamp Chain 60 is then moved forwardly grinding position and the sharpening operation is repeated as set forth above. It is to be noted that the cutting chain which I have shown in Fig. 6 is made up of four different types of .cutting teeth, as previously described, therefore, each fourth tooth is identical in construction. Consequently, I prefer to grind the cutting chain shown in Fig, 6 by grinding each fourth tooth until I reach the end of the chain. Then, in order to sharpen tooth Ill (and each fourth successive tooth thereafter) it is necessary to loosen screw .36 and re-adjust turntable 34 rotatively relative to casting It) so that the face angle I28 of tooth ill will be flat against the side face of grinding wheel 52. Thus it can be seen that it will be necessary to adjust turntable 34 rotatively relative to casting l0 four times in order to grind all of the teeth of cutting chain 64. It can be seen that if cutting chain 04 were made. up of teeth all of which had the same face angles I28, then turntable 34 would only have to be retatively adjusted once for sharpening all of the teeth of the entire chain and I do not wish to be limited to a process of sharpening a cutting chain made up of teeth having four different face angles, as shown in Fig. 6.

Referring to Figs. 9 and 10 I have shown a modified form of my invention in which circular saw blades may be sharpened as readily as link-toothed cutting chains. The turntable 34a is in the form of a segment and has arcuate rib 35a, shown in dotted lines in Fig. .9. The, segment 34a'is securely fastened relative :to casting I0 by means of clamp bar 40 in the manner hereinbefore described. Segment 34a is. likewise rotatively adjustable relative to casting l0 in the same manner as hereinbefore described.

.Secured to the end face of segment ,34aby means of bolts 202 is a downwardly depending. casting 20!.

A circular saw blade"203, a part only of whichis shown in'Fig. 9, is supported against the casting 10 by means of the clamping assemblage 204. i

The saw blade 20.3 is provided with .a' central hole (not shown) which may be circular or other shape. The saw blade 203 is mounted relative to casting 20l by removing thumb screw 120.5 and manually removingspring'206 and collar 209. The saw blade 203 is then insertedonto bolt memher 208. The collar 201, .spring 208and thumb screw 205 are then reassembled onto 'bolt'208as shown in Fig. 10. Collar 201 has a conical piloting surface '209 which is received inthe central opening in the sawblade and locates said'blade in a fixed axial position relative to casting20l.

When it is desired to sharpen saw blades of various diameter-s, thumb screw 2 ll] mayzibe' loosened and bolt member 208 may be moved'up and-down within the limits of slot 2| I. Screw- 210 is then 7 retightened and annular shoulder 12 i 2" on bolt member 208 abuts-the wall of casting 2-0I on either side of slot 2H andbolt 2'08 isfirmly secured in a fixed position relative to casting 20L Collar 201 is slidably mountedon bolt member 208 and saw blade 203 is biased against casting 20 I by means of compression spring 206 which is always under tension. It willbe noted that casting 20! has a rib 215 extending about its entire periphery permitting ample bearing surfaceffor the face of the saw blade to rest against A second rib 2H3 provides a bearing surface for'the central region of the saw blade. It will be noted; howeventhat rib 216. is shallower in depth than rib 2l5, consequently, the face of thesaw blade is biased more firmly against rib2l 5 thanagainst relative .to casting 20! by loosening wing nut 2l9.

When wing nut 219 is retightened, locating'finger lllla is anchored in a fixed position. 'When one tooth is sharpened, saw blade 203 is manually retracted axially of bolt 208 against the tension of spring 206, then rotated until the next tooth to be sharpened is in approximate position (as determined by locating finger U la) then the saw 7 blade is released and permitted to move axially of bolt 2081until it is again biased against rib, 215. Then blade 203 is further rotated slightly,

until finger l Ma bottoms at the base of the saw tooth as shown in Fig.9. The sharpening operationis then performed in thesame manner as in sharpeninga link-toothed cutting chain.

Having thus described my invention, what I" claim is: d i

1. A device for sharpening saw. teeth compris- "mg a: support member having an upright por-'- tion,a-.pair of parallel rods secured to the upper end of the upright and extending outwardly therefrom, a grinding wheel suspended from said rods and removably secured thereto so as to be longitudinally adjustable of said rods. a bracket member pivotally mounted relative to the upright whereby to be moved toward and away from the grinding wheel, a turntable rotatively adjustable relative to the bracket member and supported thereby, adjustable means secured to the bracket member and cooperating with the support member for limiting the upward movement of the bracket member relative to the support member, a rod adjustably mounted on the support member, said bracket member being pivotally mounted on said rod and movable therewith in anaxial direction whereby to adjust the position of the saw teeth relative to the grinding wheel and said saw teeth being positioned on the turntable and being sharpened by manual movement of the turntable and bracket member toward the grinding wheel.

2. A device for sharpening saw teeth comprising a support member having an upright portion, a pair of parallel rods secured to the upper end of the upright and extending outwardly therefrom, a grinding wheel suspended from said rods and removably secured thereto so as to be longitudinally adjustable of said rods, a bracket member pivotally mounted relative to the upright whereby to be moved toward and away from the grinding wheel, a turntable rotatively adjustable relative to the bracket member and supported thereby, adjustable means secured to the bracket member and cooperating with the support memher for limiting the upward movement of the bracket member relative to the support member, a second adjustment means secured to the bracket member and cooperating with the support member for limiting the downward movement of the bracket member relative to the support member, said saw teeth being positioned on the turntable and being sharpened by manual movement of the turntable and bracket member toward the grinding wheel.

3. A device for sharpening saw teeth comprising a support member, a grinding wheel carried thereby, a bracket member carried by the support member and movable relative thereto in a direction upwardly and downwardly relative to the grinding wheel, said bracket member also being movable in a. rectilinear direction from side to side relative to the grinding wheel, a turntable carried by the bracket member and rotatively adjustable relative thereto, a wall extending upwardly from the turntable, a carrying member secured to the wall and rotatively adjustable relative thereto and means associated with the carrying member for temporarily anchoring the saw tooth to be sharpened.

4. A device as described by claim 3 wherein a finger member is pivotally mounted on the carrying member. whereby to locate the saw tooth to be sharpened before said tooth is temporarily anchored.

5. A device as described by claim 3 wherein the means for temporarily anchoring the saw tooth to be sharpened includes a block, a spring normally urging said block in tooth anchoring direction, and a handle having connection with the block for retractim said block away from said saw tooth.

6. A device for sharpening saw teeth as described in claim 3 wherein a finger member is movably secured to the carrying member, whereby to locate the saw tooth to be sharpened before said tooth is temporarily anchored and a spring associated with said finger member for retracting same after the saw tooth is located.

10 7. A device as described by claim 3 wherein a pair of bars are mounted on the carrying member in spaced relation, said tooth anchoring means being movable within the space between said bars .and being guided thereby.

8. A saw tooth sharpening device comprising a frame member having an upright wall, a pivot rod extending through the upright wall and axially adjustable relative thereto, a second frame member pivotally mounted on said pivot rod, an adjustable stop member secured to the second frame member and adapted to engage the upright wall whereby to limit the upward travel of the second frame member, a pair of parallel rods secured to the upper end of the upright wall and extending outwardly therefrom, a grinding wheel removably secured to the parallel rods and adjustable axially of said rods, a turntable rotatably supported on the second frame member whereby angular adjustment of the turntable relative to the grinding wheel is obtained, means carried by the turntable for supporting the saw, teeth to be sharpened and means for locating the saw teeth relative to the grinding wheel preparatory to the sharpening thereof.

9. A saw tooth sharpening device as set forth in claim 8 wherein a counterbalancingspring extends between the second irame member and the parallel rods.

10. A tooth-anchoring device for a sharp ening machine comprising a support block, an upwardly extending Wall on the support block, a pair of bars spaced from each other and adjustably secured to the support block, said bars being normally in longitudinal alignment with each other and one of the side faces of each bar being opposed to and spaced from the wall on the support block whereby to form a channel, a movable block mounted in the space defined between the ends of the bars, means carried by the support'block for moving the movable block toward and away from the wall onthe support block, whereby to 1 anchor a cutting chain against the wall on thea support block.

11. A tooth-anchoring device for a sharpeningmachine as defined by claim 10 wherein yieldable means are associated with the movable block for normally urging said movable block in chain anchoring direction. 1 i

12. A tooth-anchoring device for a sharpening machine as defined by claim 10 wherein a lever is adjustably connected to the movable block for retracting the movable block away from the wall on the support block and for maintaining the movable block in retracted position.

13. A tooth-anchoring device for a sharpening machine comprising, a support member for supporting a cutting chain to be sharpened, a mov able block carried by the support member and adapted to engage the cutting chain for temporarily anchoring said chain relative to the support member, an upwardly extending wall portion on said support member, a rod extending through said wall portion and having screw-threaded engagement with the movable block, a lever pivotally secured to the outer end of the rod, said lever having one end in engagement with the wall portion of the support member, yieldable means extending between the movable block and wall portion for normally urging the movable block in chain clamping direction, and said lever being adapted for retracting the movable block away from the cutting chain.

14. A tooth-locating device for a sharpening machine comprising, a support member for supr 11 porting a cutting chain, said support member having an outwardly extending portion, a pivot rod jou'rn'aled through said outwardly extending portion, a bracket having a'pa'ir of arms embrac ing the outwardly extending portion, each arm being mounted on the pivot rod, said bracket member having a body portion extending between the arms, a finger extending outwardly from the 7 prised of an L-shaped bracket, a pair of spaced arms protruding outwardly from one wall of the bracket, said arms having connection with the primary supporting member so as to be adjustable pivotally relative to said primary supporting member and also adjustable laterally relative to said primary supporting member, resilient counterbalancing means extending between the primary supporting member and the second wall of the L-shaped bracket, a turntable rotatively carried by the second wall of the L-shaped bracket and means carried by the L-shaped bracket for releasably securing the turntable to the second wall of the L-shaped bracket.

1 manual movement ofthe turntable" and bracket member toward the grinding wheel.

17. A sharpening device as described inelaim 16 wherein a pair of adjustable stop members are secured to a wall of the L-shaped bracket for contacting the primary support member, thereby limiting the extent of the pivotal movement of the L-shaped bracket relative to the primary support member.

18. A device for sharpening saw teeth comprising an upright support, a horizontalsupport mounted adjacent to the upper end of the up .right support, a grinding wheel suspended from the horizontal support and movable longitudinally along the horizontal support, the grinding wheel Number Name "Date 338,187 Rogers Mar. 30; 1836 381,775 Hall'aday Apr. 24, 1888f 437,929 King Oct. 7, 1890 831,693 Wismar' Sept. 25, 1906- 1377384 Heryngfel'et al. May 10, 1921 1,853,245 Wardwel'l Apr. 12, 193-2 1,909,832 Jirka May '16, 1933'- l,966',364' Thrasher July 10, 1934 2,115,712 Gavin May'3, 1938 2,156,034 Thomas Apr; 25, 1939 2 ,21'7,145 Sti'h'l Oct. 8, 1940 2,318,456 Blum" May 4, 19433 FOREIGN PATENTS Number Country Date 7 21,655 -Great Britain Sept. 25, 1913 218,430 Switzerland Apr. 1, 1942 670,747 Germany Jan. 26, 1939 being removable from the horizontal support, abracket member pivotally mounted relative to the upright whereby to be moved toward and away from the grindingwheel, a turntable rotativelyf adjustable relative to the bracket member andsupported thereby, adjustable means secured to the bracket member and cooperating with'the support member for limiting the upward move 0 ment of the bracket member relative to the sup port member, a rod ad-justably mounted on the said bracket member being pivotally mounted on said rod and movable supportmember;

therewith in anaxial" direction whereby to adjust the position of the saw teeth relative .tothe grinding wheel and said saw teeth being positioned on the turntable and being sharpened by ARTHUR; WILLIAM-MALL.

1 REFERENCES GITED The following-references are of record in the file of this patent: V UNITED STATES PATENTS OTHER REFERENCES A Treatise on Tool Room Grinding, copyright 1937, by The Car-borundum C0., Niagara Falls,

New York. 

